This invention relates to a turbine machine including a rotatable liquid collection ring and to a process for liquid cooling the buckets of a turbine rotor.
Kydd, in U.S. Pat. Nos. 3,446,481 and 3,736,071, dicloses open-circuit liquid cooled turbines wherein liquid content of hot coolant fluid discharged from the turbine buckets is thereby thrown into an annular slot in register therewith in the wall of the turbine casing.
One problem arising in the operation of open circuit liquid cooled turbines, especially those employing high speed liquid cooled rotors, is erosion of stationary parts against which high speed jets of spent liquid coolant impinge, resulting ultimately in erosive wear thereof. Such stationary parts typically include, for example, the turbine casing.
It has now been found by practice of the present invention that this problem can be substantially minimized by providing a rotatable annular ring intermediate the casing and open circuit liquid-cooled rotor assembly. The ring includes a trough assembly so composed and arranged that liquid coolant impinging thereon is contained or temporarily held therein as a film and the ring rotates in response to such impingement. Provision is made for the ring speed to be significantly less than the rotor speed such that erosion of the casing by the coolant leaving the ring is substantially reduced relative to the amount of erosion occuring without such ring being provided.